ATR and nonpapillary renal cell carcinoma: Given that we identified numerous signatures of DNA damage, including the Reactome term “activation of ATR,” in response to replication stress as features of mouse and human ccRCC, it is notable that the 2 ATRi showed IC50 values that were 100- to 1,000-fold lower than the ATMi and DNA-PKi in ccRCC cell lines (Figure 3A).